Quantum communication method

Abstract

The invention provides a quantum communication method. The method comprises the following steps: acquiring a service matrix formed by a plurality of pieces of communication service information by utilizing a central controller, wherein the communication service information comprises a sending end, a receiving end and a plurality of initial entanglement connection numbers; solving the linear programming problem function to obtain a target entanglement connection number corresponding to each piece of communication service information; constructing a quantum communication network based on the number of the target entangled links and the number of the entangled links, wherein the position and the number of entangled photon sources are determined based on the number of the target entangled links; the central controller is utilized to respond to the entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route are constructed, and the first entanglement links comprise communication links formed between a plurality of first target repeaters and a target sending end and between the first target repeaters and a target receiving end; and the target sending end transmits the transmission information to the target receiving end by using the first entanglement route and the plurality of first entanglement links.

Description

Technical Field

[0001] The present disclosure relates to the field of quantum communication technology, and more specifically, to a quantum communication method. Background Art

[0002] The quantum entanglement distribution system is a system that uses the characteristics of quantum entanglement to distribute photons in the EPR entangled state to the source node and destination node in the communication request. At present, quantum computers are mainly used to achieve encrypted secure communication and solve complex problems such as large-scale factorization and discrete logarithm problems. In this process, a quantum computer needs to establish a quantum entanglement connection with other quantum computers, that is, the two quantum computers each store a photon in the EPR entangled state with each other to achieve the purpose of communication or calculation. Therefore, in the quantum entanglement distribution system, photons need to be distributed to the corresponding quantum computers through physical links. However, due to factors such as link absorption and signaling protocols, the success rate of photon transmission decreases exponentially with the transmission distance. In order to overcome this limitation, it is necessary to connect quantum computers and quantum repeaters to form a quantum data network to support distributed quantum computing and improve the success rate of entanglement connection creation.

[0003] In the process of realizing the concept of the present disclosure, the inventors found that there are at least the following problems in the related technology: the existing process of establishing entangled routing takes a long time, and the related technology will change the position of the entangled photon source in real time, thereby increasing communication delay. Summary of the invention

[0004] In view of this, an embodiment of the present disclosure provides a quantum communication method, including:

[0005] Using a central controller to obtain a service matrix composed of a plurality of communication service information, wherein one of the communication service information includes a transmitting end, a receiving end, and a plurality of initial entangled connection numbers;

[0006] Solving the linear programming problem function using a linear programming solver to obtain the target number of entangled connections corresponding to each of the above communication service information, wherein the above linear programming problem function is constructed based on the above service matrix;

[0007] A quantum communication network is constructed based on the plurality of target entangled connection numbers and the plurality of entangled link numbers, wherein the quantum communication network comprises the plurality of transmitting ends, the plurality of receiving ends, the plurality of repeaters, and at least one entangled photon source connected to the repeaters, and the positions and the number of the entangled photon sources are determined based on the target entangled connection numbers;

[0008] Using the central controller to respond to the entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route are constructed, wherein the first entanglement route includes a target sending end and a target receiving end, and the first entanglement link includes communication links respectively constructed between a plurality of first target repeaters and the target sending end and the target receiving end;

[0009] The target sending end transmits the transmission information to the target receiving end by using the first entangled route and the plurality of first entangled links.

[0010] According to an embodiment of the present disclosure, a linear programming problem function is solved using a linear programming solver to obtain a target number of entangled connections corresponding to each of the above communication service information, including:

[0011] The above linear programming problem function is processed based on the network flow conservation condition to obtain a relaxed linear programming problem function;

[0012] The above-mentioned linear programming solver is used to solve the above-mentioned relaxed linear programming problem function to obtain multiple above-mentioned target entanglement connection numbers.

[0013] According to an embodiment of the present disclosure, a quantum communication network is constructed based on a plurality of the above-mentioned target entanglement connection numbers, including:

[0014] For each of the above communication service information, determining the number of entangled photon sources required for the above communication service information according to the above target number of entangled connections;

[0015] The above-mentioned number of entangled photon sources are distributed to the repeaters corresponding to the above-mentioned communication service information to complete the construction of the above-mentioned quantum communication network.

[0016] According to an embodiment of the present disclosure, the central controller is used to respond to an entanglement connection request to determine a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, including:

[0017] In response to the entanglement connection request, determining the target sending end, the target receiving end and the target entanglement connection quantity;

[0018] Determine, by the central controller, the number of first entanglement links established between the first target repeater and the first target repeater and the target transmitting end and the target receiving end, respectively, according to the target transmitting end, the target receiving end and the number of target entanglement connections;

[0019] The number of the first entangled links is sent to the first target repeater, so that the first target repeater constructs the first entangled links of the number mentioned above.

[0020] According to an embodiment of the present disclosure, the central controller is used to respond to an entanglement connection request to construct a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, further comprising:

[0021] storing resource allocation information corresponding to the entanglement connection request, the target transmitting end, the target receiving end, the target entanglement connection quantity, the first target repeater and the quantity of the first entanglement link in the central controller; and / or

[0022] After the first target repeater successfully constructs the above number of first entangled links, successful construction information is fed back to the central controller.

[0023] According to an embodiment of the present disclosure, the quantum communication method further includes:

[0024] In a case where the number of entangled photons that can be transmitted by the above number of first entangled links is less than the number of entangled photons that need to be transmitted by the above entangled connection request, determining at least one receiving end as a second target repeater;

[0025] determining a repeater associated with the at least one receiving end as a second target repeater;

[0026] Constructing a second entangled route and a plurality of second entangled links respectively according to the target transmitting end, the plurality of second target repeaters and the target receiving end;

[0027] The target transmitting end is utilized to transmit the remaining entangled photons to the target receiving end through the second entangled routing and multiple second entangled links, wherein the remaining entangled photons represent the entangled photons remaining after the entangled photons required to be transmitted by the entangled connection request are transmitted by the first entangled link.

[0028] According to an embodiment of the present disclosure, the target transmitting end transmits the transmission information to the target receiving end by using the first entangled routing and the plurality of first entangled links, including:

[0029] The central controller determines a quantum node according to the first entangled link, wherein the quantum node includes the first target repeater;

[0030] Performing quantum entanglement exchange on the quantum nodes to splice the plurality of first entangled links into a target link;

[0031] The transmission information is transmitted to the target receiving end using the target link.

[0032] According to an embodiment of the present disclosure, when the number of the first target repeater is one, performing quantum entanglement exchange on the quantum node to splice a plurality of the first entangled links into a target link includes:

[0033] Generate two first photon pairs using an entangled photon source connected to the first target repeater, wherein the first photon pairs include an entangled first photon and a second photon;

[0034] Using the first target repeater, the first photons in the two first photon pairs are respectively sent to a target transmitting end and a target receiving end;

[0035] The first target repeater is used to perform quantum entanglement exchange on the second photon of the two first photon pairs, so as to splice the first entangled link between the target transmitting end and the first target repeater and the first entangled link between the first target repeater and the target receiving end into a target link between the target transmitting end and the target receiving end.

[0036] According to an embodiment of the present disclosure, when the number of the first target repeaters is N, quantum entanglement exchange is performed on the quantum nodes to splice a plurality of the first entangled links into a target link, including:

[0037] When i is not equal to N, generating a second photon pair using an entangled photon source connected to the i-th first target repeater, wherein the second photon pair includes an entangled third photon and a fourth photon;

[0038] Using the i-th first target repeater, the third photon is sent to the target transmitting end or the i-1-th first target repeater associated with the first target repeater;

[0039] Using the i-th first target repeater to perform quantum entanglement exchange on the first photon set or the second photon set, a third entangled link is obtained, wherein the third entangled link represents a link between the target transmitter and the N-th first target repeater, the first photon set includes the third photon and the fourth photon, and the second photon set includes the fourth photon and the fifth photon;

[0040] When i is equal to N, generating two third photon pairs using an entangled photon source connected to the i-th first target repeater, wherein the third photon pair includes the entangled fifth photon and the sixth photon;

[0041] Using the i-th first target repeater, two fifth photons are sent to the i-1-th first target repeater and the target receiving end respectively;

[0042] The i-th first target repeater is used to perform quantum entanglement exchange on the two sixth photons to obtain a fourth entangled link, wherein the fourth entangled link represents a link between the target transmitting end and the target receiving end.

[0043] According to an embodiment of the present disclosure, using the target link to transmit the transmission information to the target receiving end includes:

[0044] Observe the system state information between the first photon and the quantum bit received by the target transmitting end, wherein the quantum bit represents the transmission information;

[0045] Transmitting the system status information to the target receiving end through the central controller or the external computer, wherein the central controller or the external computer is connected to the target sending end and the target sending end;

[0046] The target receiving end obtains the quantum bit sent by the target transmitting end according to the first photon received by the target receiving end and the system state information.

[0047] According to the embodiments of the present disclosure, by modeling a business matrix composed of multiple communication business information into a linear programming problem function, the target number of entangled connections for each communication business information can be determined for the linear programming problem function, so that a quantum communication network can be constructed based on the target number of entangled connections. At this time, the corresponding first entangled route and the first entangled link can be constructed before the target transmitting end starts to send the transmission data, so as to transmit the transmission information to the target receiving end. Since the entangled photon source is set at a fixed position in the quantum communication network before transmission, an entangled connection with a small communication delay can be quickly established under any entangled connection request and a good network throughput can be guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0049] Figure 1 The flowchart of the quantum communication method according to the embodiment of the present disclosure is schematically shown;

[0050] Figure 2 The framework diagram of the initial quantum data network according to the embodiment of the present disclosure is schematically shown;

[0051] Figure 3 The schematic diagram shows a framework diagram of a quantum communication network according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0052] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0053] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0054] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0055] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0056] Quantum data networks usually consist of a quantum network part and a classical network part. The quantum network part mainly includes quantum computers, quantum repeaters, optical fibers and entangled photon sources. Quantum computers and quantum repeaters have similar structures and functions. They both have limited quantum memory for storing photons, can observe the state of photons and perform operations such as quantum entanglement exchange. The two can be collectively referred to as quantum nodes. The main difference is that quantum computers have the need to establish entangled connections with other quantum computers, while quantum repeaters do not have this need. Optical fibers are used to achieve interconnection between quantum nodes, and they provide quantum channels necessary for photon transmission. Entangled photon sources are usually placed on quantum nodes, and their function is to generate photon pairs in the EPR entangled state for the establishment of entangled connections. As a supplement to quantum networks, classical networks complete some functions that quantum networks cannot complete, such as sending measurement results and transmitting control signals.

[0057] When establishing an entangled connection between two quantum nodes (distributing quantum entanglement), the existing technology usually first searches for a path from the source node to the destination node (called entangled routing); then the quantum nodes on the path use an entangled photon source to generate photons and distribute them to adjacent nodes, thereby establishing several entangled links (or external connections) on each edge of the path; finally, the intermediate nodes on the path perform quantum entanglement exchange to splice the entangled links into an end-to-end entangled connection.

[0058] In the above process, the prior art assumes that each node has enough entangled photon sources, or dynamically changes the placement of entangled photon sources according to connection requests when the number of entangled photon sources is limited. However, due to the high price of entangled photon sources, it is difficult to deploy them on a large scale. At the same time, the change of the location of the entangled photon source will cause a very large communication delay. In addition, for different connection requests, the related technology needs to calculate different entangled routes online, which makes it take a long time to establish an entangled connection. Therefore, it is difficult to apply this technology to quantum entanglement distribution.

[0059] In view of this, an embodiment of the present disclosure provides a quantum communication method. The method includes using a central controller to obtain a service matrix composed of multiple communication service information, wherein one communication service information includes a transmitter, a receiver and multiple initial entangled connection numbers; using a linear programming solver to solve a linear programming problem function to obtain a target entangled connection number corresponding to each communication service information, wherein the linear programming problem function is constructed based on the service matrix; constructing a quantum communication network based on multiple target entangled connection numbers, wherein the quantum communication network includes multiple transmitters, multiple receivers, multiple repeaters and at least one entangled photon source connected to the repeaters, and the positions and numbers of the entangled photon sources are determined based on the target entangled connection numbers; using the central controller to respond to an entangled connection request, constructing a first entangled route corresponding to the entangled connection request and multiple first entangled links corresponding to the first entangled route, wherein the first entangled route includes a target transmitter and a target receiver, and the first entangled link includes a communication link formed between multiple first target repeaters and the target transmitter and the target receiver respectively; the target transmitter transmits the transmission information to the target receiver using the first entangled route and the multiple first entangled links.

[0060] Figure 1 The flowchart of the quantum communication method according to the embodiment of the present disclosure is schematically shown.

[0061] like Figure 1 As shown, the quantum communication method includes operations S101 to S105.

[0062] In operation S101, a service matrix composed of a plurality of communication service information is acquired by using a central controller, wherein one communication service information includes a transmitting end, a receiving end, and a plurality of initial entangled connection numbers;

[0063] In operation S102, a linear programming problem function is solved by using a linear programming solver to obtain a target number of entangled connections corresponding to each communication service information, wherein the linear programming problem function is constructed based on a service matrix;

[0064] In operation S103, a quantum communication network is constructed based on multiple target entangled connection numbers and multiple entangled link numbers, wherein the quantum communication network includes multiple transmitting ends, multiple receiving ends, multiple repeaters, and at least one entangled photon source connected to the repeaters, and the position and number of the entangled photon source are determined based on the target entangled connection number;

[0065] In operation S104, a first entangled route corresponding to the entangled connection request and a plurality of first entangled links corresponding to the first entangled route are constructed by the central controller in response to the entangled connection request, wherein the first entangled route includes a target transmitting end and a target receiving end, and the first entangled link includes communication links respectively formed between a plurality of first target repeaters and the target transmitting end and the target receiving end;

[0066] In operation S105 , the target transmitting end transmits transmission information to the target receiving end by using the first entangled route and the plurality of first entangled links.

[0067] According to an embodiment of the present disclosure, communication service information can be constructed according to the actual number of sending ends and receiving ends. For example, a communication service information can be constructed for sending end 1 and receiving end 1, wherein the communication service information corresponds to multiple initial entanglement connection numbers, and the initial entanglement connection number can be an integer such as 1, 2, 3, etc.

[0068] According to an embodiment of the present disclosure, multiple communication service information are constructed into a corresponding service matrix, so that the coverage network corresponding to the service matrix is ​​modeled into a linear programming problem function, and then the linear programming problem function is solved using a linear programming solver to obtain a function solution, which includes a quantity limit on the number of entangled connections for each communication service information, that is, the target number of entangled connections.

[0069] According to the embodiments of the present disclosure, after determining the target number of entangled connections for each communication service information, a corresponding number of entangled photon sources can be set on the repeater between the transmitting end and the receiving end according to the target number of entangled connections. For example, if the target number of entangled connections is 2, then 2 entangled photon sources can be set on the repeater between the transmitting end and the receiving end. Thus, a quantum communication network can be constructed.

[0070] According to an embodiment of the present disclosure, after the construction is completed, the transmitter sends an entanglement connection request to the central controller, and the central controller responds to the request to construct a corresponding first entanglement route and a plurality of first entanglement links corresponding to the first entanglement route, for example, a first entanglement link between the transmitter 1 and the repeater 1, a first entanglement link between the repeater 1 and the receiving end 1, and a first entanglement route between the transmitter 1 and the receiving end 1. After this, the transmission information sent by the transmitter 1 can be transmitted to the receiving end 1 through the first entanglement route and the first entanglement link.

[0071] According to the embodiments of the present disclosure, by modeling a business matrix composed of multiple communication business information into a linear programming problem function, the target number of entangled connections for each communication business information can be determined for the linear programming problem function, so that a quantum communication network can be constructed based on the target number of entangled connections. At this time, the corresponding first entangled route and the first entangled link can be constructed before the target transmitting end starts to send the transmission data, so as to transmit the transmission information to the target receiving end. Since the entangled photon source is set at a fixed position in the quantum communication network before transmission, an entangled connection with a small communication delay can be quickly established under any entangled connection request and a good network throughput can be guaranteed.

[0072] According to an embodiment of the present disclosure, a linear programming problem function is solved using a linear programming solver to obtain a target number of entangled connections corresponding to each communication service information, including:

[0073] The linear programming problem function is processed based on the network flow conservation condition to obtain the relaxed linear programming problem function;

[0074] The relaxed linear programming problem function is solved using a linear programming solver to obtain multiple target entanglement connection numbers.

[0075] According to an embodiment of the present disclosure, the linear programming problem function is an integer linear programming problem, and there cannot be decimals for the target number of entangled connections in a quantum communication network. Therefore, it is necessary to remove the integer constraints in the planning problem, and use network traffic conservation conditions, quantum resource constraints, etc. to process it, so as to obtain a relaxed linear programming problem function, and use a linear programming solver to solve the problem function to obtain the target number of entangled connections corresponding to each communication service information, wherein the quantum resource constraints include storage space of quantum nodes, the number of entangled photon sources, etc.

[0076] Figure 2 The framework diagram of the initial quantum data network according to an embodiment of the present disclosure is schematically shown. Figure 3 The schematic diagram shows a framework diagram of a quantum communication network according to an embodiment of the present disclosure.

[0077] According to an embodiment of the present disclosure, a quantum communication network is constructed based on multiple target entanglement connection numbers, including:

[0078] For each communication service information, determining the number of entangled photon sources required for the communication service information according to the target number of entangled connections;

[0079] Distribute a number of entangled photon sources to repeaters corresponding to the communication service information to complete the construction of the quantum communication network.

[0080] According to an embodiment of the present disclosure, the target number of entangled connections is the number of photon pairs required. When the number of photon pairs is determined, the number of entangled photon sources required for the repeaters related to the communication service information is determined, and this number of entangled photon sources is distributed to the repeaters corresponding to the communication service information, thereby completing the construction of the quantum communication network and maximizing the expected throughput of the network and the fairness between node pairs, wherein a node refers to any device among the transmitting end, the receiving end and the relay end.

[0081] According to the embodiments of the present disclosure, Figure 2 The initial quantum data network shown in the figure has a total of 3 quantum computers Q 1 , Q 2 , Q 3 (Any one of them can be used as a transmitter and a receiver), 3 quantum repeaters R 1 , R 2 and R 3 Assume that only 6 entangled photon sources can be placed. By using the method disclosed in the present invention, the entangled photon sources are allocated to the repeaters corresponding to the communication service information, thereby obtaining Figure 3 The quantum communication network shown.

[0082] It should be noted that Figure 3 Each triangle connected to the repeater R represents a source of entangled photons.

[0083] According to an embodiment of the present disclosure, a central controller is used to respond to an entanglement connection request to construct a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, including:

[0084] In response to the entanglement connection request, determining a target sending end, a target receiving end, and a target entanglement connection quantity;

[0085] Determine, by means of a central controller, the number of first entanglement links established between the first target repeater and the first target repeater and the target transmitting end and the target receiving end, respectively, according to the target transmitting end, the target receiving end and the number of target entanglement connections;

[0086] The number of the first entanglement links is sent to the first target repeater, so that the first target repeater constructs the number of the first entanglement links.

[0087] According to an embodiment of the present disclosure, when the target transmitting end in the quantum communication network sends an entanglement connection request, the central controller determines the corresponding target receiving end and the number of entanglement connections to be sent this time based on the entanglement connection request, thereby determining the number of first entanglement links established between every two adjacent nodes (i.e., the first target repeater and the target transmitting end and the target receiving end, respectively), and the central controller sends it to the corresponding node (i.e., the first target repeater), thereby enabling the first target repeater to establish a corresponding number of first entanglement links.

[0088] According to an embodiment of the present disclosure, a first entangled route corresponding to the entangled connection request and a plurality of first entangled links corresponding to the first entangled route are constructed by using a central controller in response to the entangled connection request, and further comprising:

[0089] storing resource allocation information corresponding to the entanglement connection request, the target transmitting end, the target receiving end, the target entanglement connection quantity, the first target repeater, and the quantity of the first entanglement link in the central controller; and / or

[0090] After the first target repeater successfully constructs the first number of entangled links, successful construction information is fed back to the central controller.

[0091] According to an embodiment of the present disclosure, in the process of allocating resources, the central controller determines the entanglement connection request, the corresponding target transmitter, the target receiver, the number of target entanglement connections, the first target repeater, and the number of first entanglement links, and other resource allocation information is stored in the central controller in the form of a log.

[0092] According to an embodiment of the present disclosure, after the first target repeater and other nodes successfully establish the first entanglement link, each node needs to feedback to the central controller whether it is successful, so that the central controller can send transmission information after determining that all relevant nodes have successfully established the entanglement link.

[0093] In one embodiment, the node establishes a first entangled link through an entangled photon source. For example, in the first entangled routing (Q 1 ,R 1 ,Q 2 ), the first entangled links created are (Q 1 ,R 1 ) and (R 1 ,Q 2 ). At this time, the first entanglement link successfully created is fed back to the central controller.

[0094] According to an embodiment of the present disclosure, the quantum communication method further includes:

[0095] In a case where the number of entangled photons that can be transmitted by the first entangled link is less than the number of entangled photons that need to be transmitted for the entangled connection request, determining at least one receiving end as a second target repeater;

[0096] determining a repeater associated with at least one receiving end as a second target repeater;

[0097] respectively constructing a second entangled route and a plurality of second entangled links according to a target transmitting end, a plurality of second target repeaters and a target receiving end;

[0098] The target transmitting end transmits the remaining entangled photons to the target receiving end through the second entangled routing and multiple second entangled links, wherein the remaining entangled photons represent the entangled photons remaining after the entangled photons required to be transmitted by the entangled connection request are transmitted by the first entangled link.

[0099] According to an embodiment of the present disclosure, for example, the transmitting end Q 1 Want to give the receiving end Q 2 Send entangled photons, that is, the first entangled route is (Q 1 ,R 1 ,Q 2 ), if the number of entangled photons that can be transmitted by the first entangled link is less than the number of entangled photons required to be transmitted by the entangled connection request, and the other receiving end Q 3 The quantum resources are relatively abundant. At this time, in order to fully utilize the quantum resources and improve the network throughput, the central controller calculates the second entanglement route online according to the remaining quantum resources. Assume that the obtained second entanglement route is (Q 1 ,R 3 ,Q 3 ,R 2 ,Q 2 ), where the receiving end Q 3 , Repeater R 3 , R 2 is determined as the second target repeater. (Q 1 ,R 3 )、(R 3 ,Q 3 )、(Q 3 ,R 2 )、(R 2 ,Q 2 ) are the second entanglement links.

[0100] The central controller then calculates the repeater R 3 and R 2 The number of entanglements that should be distributed, that is, the number of (Q 1,Q 3 ) and (Q 3 ,Q 2 )’s entangled links, thereby utilizing the second entangled routing to send the entangled photons that the first entangled routing cannot send.

[0101] In one embodiment, time can be divided into several segments. At the beginning of each time period, a service matrix may arrive, and at this time, the service requirements need to be met as much as possible before the time runs out. Specifically, within a time period, the first entangled route that has been calculated long ago is first used to determine the entangled link that needs to be constructed, but the construction has not started at this time; the central controller calculates the second entangled route in real time according to the remaining resources, and then calculates the second entangled link based on this, and then sends the construction quantity of the first entangled link and the second entangled link to the relevant repeater.

[0102] However, for some service matrices, even through the second entanglement routing, it is not necessarily possible to successfully transmit all photons to the receiving end within this time period. In addition, the second entanglement routing may contain multiple entanglement paths.

[0103] According to an embodiment of the present disclosure, a target transmitting end transmits transmission information to a target receiving end using a first entangled route and a plurality of first entangled links, including:

[0104] The central controller determines a quantum node according to the first entangled link, wherein the quantum node includes a first target repeater;

[0105] Performing quantum entanglement exchange on the quantum node to splice the plurality of first entangled links into a target link;

[0106] The target link is used to transmit the transmission information to the target receiving end.

[0107] According to an embodiment of the present disclosure, for a plurality of first entangled links, corresponding quantum nodes are determined. For example, the first entangled link is (Q 1 ,R 1 )、(R 1 ,Q 2 ), the quantum node determined at this time is R 1 , and send it to the first target repeater R 1 , thereby making the first target repeater R 1 Perform quantum entanglement exchange, thereby converting the first entanglement link (Q 1 ,R 1 )、(R 1 ,Q 2 ) is spliced ​​into the target link (Q 1 ,Q 2 ), then the target link (Q 1 ,Q 2) transmits the transmission information to the target receiving end.

[0108] In one embodiment, when the number of the first target repeater is one, performing quantum entanglement exchange on the quantum node to splice a plurality of first entangled links into a target link includes:

[0109] Generate two first photon pairs using an entangled photon source connected to a first target repeater, wherein the first photon pairs include an entangled first photon and a second photon;

[0110] Using a first target repeater, the first photons in the two first photon pairs are respectively sent to a target transmitting end and a target receiving end;

[0111] The first target repeater is used to perform quantum entanglement exchange on the second photon of the two first photon pairs to splice the first entangled link between the target transmitting end and the first target repeater and the first entangled link between the first target repeater and the target receiving end into a target link between the target transmitting end and the target receiving end.

[0112] In another embodiment, the entangled photon source connected to the first target repeater generates only one photon pair, and sends the first photon and the second photon to the target transmitting end and the target receiving end respectively, thereby completing the establishment of the target link.

[0113] According to an embodiment of the present disclosure, when the number of first target repeaters is N, quantum entanglement exchange is performed on quantum nodes to splice multiple first entangled links into a target link, including:

[0114] When i is not equal to N, generating a second photon pair using an entangled photon source connected to the i-th first target repeater, wherein the second photon pair includes an entangled third photon and a fourth photon;

[0115] Using the i-th first target repeater to send the third photon to the target transmitting end or the i-1-th first target repeater associated with the first target repeater;

[0116] Using the i-th first target repeater to perform quantum entanglement exchange on the first photon set or the second photon set, a third entangled link is obtained, wherein the third entangled link represents a link between the target transmitting end and the N-th first target repeater, the first photon set includes the third photon and the fourth photon, and the second photon set includes the fourth photon and the fifth photon;

[0117] When i is equal to N, generating two third photon pairs using an entangled photon source connected to the i-th first target repeater, wherein the third photon pair includes an entangled fifth photon and a sixth photon;

[0118] Using the i-th first target repeater, two fifth photons are sent to the i-1-th first target repeater and the target receiving end respectively;

[0119] The i-th first target repeater is used to perform quantum entanglement exchange on the two sixth photons to obtain a fourth entangled link, wherein the fourth entangled link represents a link between the target transmitting end and the target receiving end.

[0120] According to an embodiment of the present disclosure, using a target link to transmit transmission information to a target receiving end includes:

[0121] Using the target transmitting end to observe the system state information between the first photon received by itself and the quantum bit, wherein the quantum bit represents the transmitted information;

[0122] transmitting the system status information to a target receiving end through a central controller or an external computer, wherein the central controller or the external computer is connected to the target sending end and the target sending end;

[0123] The target receiving end obtains the quantum bit sent by the target transmitting end according to the first photon received by itself and the system state information.

[0124] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A quantum communication method, comprising: Using a central controller to obtain a service matrix composed of a plurality of communication service information, wherein one of the communication service information includes a transmitting end, a receiving end, and a plurality of initial entangled connection numbers; Solving the linear programming problem function using a linear programming solver to obtain a target number of entangled connections corresponding to each of the communication service information, wherein the linear programming problem function is constructed based on the service matrix; A quantum communication network is constructed based on the multiple target entangled connection numbers and the multiple entangled link numbers, wherein the quantum communication network includes multiple transmitting ends, multiple receiving ends, multiple repeaters, and at least one entangled photon source connected to the repeater, and the position and number of the entangled photon source are determined based on the target entangled connection number; Determining, by the central controller, in response to an entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, wherein the first entanglement route includes a target transmitting end and a target receiving end, and the first entanglement link includes communication links respectively formed between a plurality of first target repeaters and the target transmitting end and the target receiving end; The target transmitting end transmits transmission information to the target receiving end by using the first entangled route and the plurality of the first entangled links.

2. The method according to claim 1, wherein: The linear programming problem function is solved by using a linear programming solver to obtain the target number of entangled connections corresponding to each of the communication service information, including: Processing the linear programming problem function based on the network flow conservation condition to obtain a relaxed linear programming problem function; The linear programming solver is used to solve the relaxed linear programming problem function to obtain multiple target entanglement connection numbers.

3. The method according to claim 1, wherein: Constructing a quantum communication network based on a plurality of the target entangled connection numbers, comprising: For each of the communication service information, determining the number of entangled photon sources required for the communication service information according to the target number of entangled connections; The number of entangled photon sources is distributed to the repeaters corresponding to the communication service information to complete the construction of the quantum communication network.

4. The method according to claim 3, wherein: The method comprises: using the central controller to determine, in response to an entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, comprising: In response to the entanglement connection request, determining the target sending end, the target receiving end and the number of entanglement connections; Determine, by the central controller, the number of first entanglement links established between the first target repeater and the first target repeater and the target transmitting end and the target receiving end respectively according to the target transmitting end, the target receiving end and the number of entanglement connections; The number of the first entangled links is sent to the first target repeater, so that the first target repeater constructs the number of first entangled links.

5. The method according to claim 4, further comprising: storing resource allocation information corresponding to the entanglement connection request, the target sending end, the target receiving end, the target entanglement connection quantity, the first target repeater, and the quantity of the first entanglement link in the central controller; and / or After the first target repeater successfully constructs the number of first entangled links, successful construction information is fed back to the central controller.

6. The method according to claim 4, further comprising: In a case where the number of entangled photons that can be transmitted by the number of first entangled links is less than the number of entangled photons that need to be transmitted by the entangled connection request, determining at least one receiving end as a second target repeater; determining a repeater associated with the at least one receiving end as a second target repeater; respectively constructing a second entangled route and a plurality of second entangled links according to the target transmitting end, the plurality of the second target repeaters and the target receiving end; The target transmitting end is utilized to transmit the remaining entangled photons to the target receiving end through the second entangled routing and multiple second entangled links, wherein the remaining entangled photons represent the entangled photons remaining after the entangled photons required to be transmitted by the entangled connection request are transmitted by the first entangled link.

7. The method according to claim 1, wherein: The target sending end transmits transmission information to the target receiving end by using the first entangled route and the plurality of the first entangled links, including: The central controller determines a quantum node according to the first entangled link, wherein the quantum node includes the first target repeater; Performing quantum entanglement exchange on the quantum node to splice a plurality of the first entangled links into a target link; The transmission information is transmitted to the target receiving end using the target link.

8. The method according to claim 7, wherein: When the number of the first target repeaters is one, performing quantum entanglement exchange on the quantum node to splice a plurality of the first entangled links into a target link includes: Generate two first photon pairs using an entangled photon source connected to the first target repeater, wherein the first photon pairs include an entangled first photon and a second photon; Using the first target repeater, the first photons in the two first photon pairs are respectively sent to a target transmitting end and a target receiving end; The first target repeater is used to perform quantum entanglement exchange on the second photon of the two first photon pairs to splice the first entangled link between the target transmitting end and the first target repeater and the first entangled link between the first target repeater and the target receiving end into a target link between the target transmitting end and the target receiving end.

9. The method according to claim 7, wherein: When the number of the first target repeaters is N, performing quantum entanglement exchange on the quantum nodes to splice a plurality of the first entangled links into a target link includes: When i is not equal to N, generating a second photon pair using an entangled photon source connected to the i-th first target repeater, wherein the second photon pair includes an entangled third photon and a fourth photon; Using the i-th first target repeater to send a third photon to a target transmitting end or an i-1-th first target repeater associated with the first target repeater; Using the i-th first target repeater to perform quantum entanglement exchange on the first photon set or the second photon set, to obtain a third entangled link, wherein the third entangled link represents a link between the target transmitting end and the N-th first target repeater, the first photon set includes the third photon and the fourth photon, and the second photon set includes the fourth photon and the fifth photon; When i is equal to N, generating two third photon pairs using an entangled photon source connected to the i-th first target repeater, wherein the third photon pairs include the entangled fifth photon and the sixth photon; Using the i-th first target repeater, two fifth photons are sent to the i-1-th first target repeater and the target receiving end respectively; The i-th first target repeater is used to perform quantum entanglement exchange on two sixth photons to obtain a fourth entangled link, wherein the fourth entangled link represents a link between the target transmitting end and the target receiving end.

10. The method according to claim 8, wherein: Transmitting the transmission information to the target receiving end using the target link includes: Using the target transmitting end to observe the system state information between the first photon and the quantum bit received by the target transmitting end, wherein the quantum bit represents the transmission information; Transmitting the system status information to the target receiving end through the central controller or the external computer, wherein the central controller or the external computer is connected to the target sending end and the target sending end; The target receiving end is used to obtain the quantum bit sent by the target transmitting end according to the first photon received by itself and the system state information.

Images